Brake



May 29, E ZIPPER U BRAKE 1 Fi led May 20, 1946 5 Sheets-Sheet 1 57 \NVEN TO R Ewm ZiPPER A T TV 8. f

MQZQ, 1945. E'ZWPER 2,376,889

' BRAKE Filed May 20, 1940 5 Shets-Shet 2 \NVENTOR U; "sv 76 Emu ZIPPER May 29, 1945. E. ZIPPER 2,376,889

BRAKE Filed May 20, 1940 5 Sheets-Sheet 4 EMIL ZIPPER INVENTOR May 29, 1945,. ZlPPER 2,376,889

' BRAKE Filed May 20, 1940 5 Sheets-Sheet 5 Di m,

\NVE'NTOR EVIMILI ZIPPER U W. (4 *MM' ATTYS.

Patented May 29, 1945 8 BRAKE Emil Zipper, Paris 16, France; vested in th Alien Property Custodian Application May 20,1940, Serial No. 336,290 In Great Britain May 23, 1939 6 Claims. ('Cl. 188-78) This invention relates to brakes and;more particularly although not essentially to brakes suitable for road vehicles such as omnibuses and to aeroplanes.

The main objects of the invention are to provide means of simple constructional form for operating brake shoes which will provide eiilcient servo action and parallel brake motion.

In order that the invention may be more clearly understood, it will now be briefly described with reference to the accompanying drawings, in which:

Figure 1 is a side elevational view of a brake made in accordance with the invention.

Figure 2 is a sectional view on the line 2-4 in Figure 1. 7

Figures is a section on the line 33 in Figure 1.

Figures 4, 5, 6 and '7 areside elevations showing modified constructions of brakes made in accordance with the invention.

Figures 8, 9, 10 and 11 are sectional views on the lines 8-8, 9--9, |-l0 and ||-|I in Figure" 7., and

Figure 12 is a side elevational view of a modifled iorm of brake made in accordance with the invention.

In Figures 1, 2 and 3:

The brake carrier I which is fixed to the axle casing has an annular flange 2 on which two axially spaced guiding rings 3 and 4 are rotatably mounted. Each of these two guiding rings has two lugs 5. 6 and 1, 8 which are-180 apart. Corresponding pivot pins I3, I4 and I5, I6 are ar' ranged rotatably in holes in these lugs. Corresponding levers 9, I0 and II, I2 are connected at one end to these pivot pins.

In each of the brake shoes 2|, 22 are two holes located adjacent their ends, in which corresponding pivot pins I1, I8 and I9, 20 have their bearings. The remaining ends of the levers 8, III, II, I2, are'connected to the last mentioned pivot pins. Slots 25 and 28, are provided in the middle of the brake shoes 2| and 22, respectively, through which pass pins '23 and 24, respectively, that are fixed in the brake vers 21 and 28 have their opposite carrier I. ends pivoted on,the pins 23 and 24 and the bolts I9 and I1, respectively.

On each of the pins I3 and I is pivoteda corresponding guiding piece 8|, '32, which can slide tangentially in corresponding cam blocks 35, 36. The sliding movement serves for the adjustment oi the brake shoes and is carried out by worms 33, 34 and worm wheels 29, 3 0. The worm wheels 29, 30, are fixed to bolts 31, 38, having their nuts in the connecting blocksy3l, 32. The cam-blocks 35, 38 are mountedon the rings the blocks 35, 36 are moved apart. The distances of the points 98 and 891mm the cam centre are equal in order to equalise the movement of the cam blocks. Return of the two rings and the brake shoes to initial positions is effected by means of the contractile spring 40.

In the construction illustrated in Figure 4, the

lugs 4|, 42 of the guiding rings ,3, 4, have slots 45, 48 in which flat sided pins 43, 44 can slide. These pins are mounted in the brake shoes 2 I, 22.

Figure 5 shows the same slotted arrangement applied to a four-shoe brake. Each of the rings 3, 4 has four lugs 41, 48, 49, 50. In the lugs are slots 55, 56, 51, in which the flat sided pins of the brake shoes can slide. The pins 61 are fixed in the brake carrier. The levers 86 are mounted on the pins 61 and on the flat sided pins 52. The

. cam block 60 hasslotted extensions reaching to the middle of the brake shoe. At thevends of these extensions are holes in which the socket 6| is borne. 1n the socket is a thread for the screw 62. A worm wheel is connected with the screw 62 which is carried by a lug 63 on the rings 3, 4. The adjustment is efiected by means of the worm 64. The return movement of the brake shoes to their normal positions is effected by means of springs 68.

In the four-shoe brake shown in Figure 6, the lugs 69, 10, 1|, 12 which are part of the guiding rings 3, 4, have holes in which the pins 13, 14, 15, 16, are rotatably mounted. In each of the brake shoes 81., 92 are two holes in which the pins 8|, 82, 83, 84 are carried. Corresponding ,ends 01' the levers 11, 18, 19, are mounted on the pins 13, 14, 15, 18 and on the pins 8|, 82, 83', 84, the pins being rotatable in the levers. The pin which is fixed in the .brake carrier passes through the slot 9| of the brake shoe 92. Corresponding ends IOI' has lugs I04 connected by pins I05 and links I06 to the pivot pin I01 carried by the brake shoes I08. The pivot pins I01 are connected by links I09 to the fixed pins IIO, the apertures in the links adjacent to the fixed pins being elongated as shown at III. The links |09 are pulled by springs H2. The. arrangement II3, 4 applies power to the ring and the spacing between the part 4 and the, lug I04 can be adjusted by the arrangement H5, H6, H1. The shoes are 9 and 4 in a manner to permit some circumierential movement but prevent any radial movement oi the blocks relative to the rings. By turning the cam 39 out of the position shown in'Fig. 1,

- connected to each other by guides II9 sliding in'guideways I20. 7

In the constructional form of the invention shown in Figure 12, a single ring |03a is provided.

This ring has 'two' radially extending lugs I04acarrying pivot pins 'I05a' oflset from each o1= cs.,

other and disposed a short distance one on one side and one on the other side of a line connecting the middle points of two brake shoes Illa.

The pins 15a are connected by links lllta each more. A short rotary movement applied to the w ring in one direction tends to collapse the toggles and force the shoes outwardly. The trailing end of each shoe is connected at Ina by a link "2a at 9a to a radially outwardly projecting lug 2a on the ring lllla, whereby a parallel action of the shoes is ensured. A spring Illa pulls on a lug l25a for returning the ring to its normal position. Other springs ma pull on the ends of the toggle links lll9a adjacent to the fixed pins a so that the elongated apertures Illa are drawn towards the trailing ends of the shoes. When the brake is applied, the braking force will tend to move the shoe in the direction of rotation of the brake drum, thereby "increasing the pressure of the shoes 'through'the leverage of the toggle link and of the links at the trailing ends of the shoes. The elongated apertures Illa permit any slight'movement ot the shoes necessary for this purpose. A powerful servo action is thus exerted on both shoes.

one link connecting the other lug to the midpoint of the other brake shoe, fixed pins, the other links of the toggle linkages connecting said pins to the mid-point oi the shoes and means to "move the ring whereby the shoes are actuated to apply the braking force through the toggle I linkages.

' 2. A brake mechanism comprising a fixed support. a plurality of brake shoes mounted circumi'erentially about the center ofsaid support and adapted to be moved outwardly into engagement with a drum of a'rotary member to be braked to produce a braking eflect, links, means pivotally connecting one end or each link to the support, means pivotally connecting the other end of each link to oneof the shoes, an actuator member carrying pins movable in a circle about the center of said support, other links each having one end connected to said pins and its other end connected to the shoes'by the means connecting the firstmentioned links to the shoes, the points of connectionofthe links to the actuator member and support being inwardly oi the point or connw tion of the'links to the shoes and the point of connection on pair oi links with a shoe lying intermediate the points of connection of said pair of linkswith the actuator and support to, produce a'servo braking ellect in one direction of rotation member to bebraked, the means connecting the links to the support including lost motion mechanism toenable slight rotation ofthe shoe with-Ithe member to be braked when rotating inthe opposite direction to produces servo eflect.

3. A brake mechanism comprising a fixed support, a plurality of brake shoes mounted circumferentially about the center of said support and 'adapted to be moved outwardly into engagement a with a drum 01' a rotary member to be braked to produce a braking effect, a pin carried by each shoe, a pair of links each having one end pivotally connected to said pin, a pin connecting the other end 01' one link to the support, a rotary actuator, 10 and apin connecting the other end or the other link to the actuator pin, the pin of the shoe lying outwardly of and between the pins oi. the support and actuator, the end of the links connected to the support pins having slots receiving said suplo port pins to provide a lost motion -connection therewith. v 4

4. A brake mechanism comprising a fixed support, a plurality of brake shoes mounted circumferentially about the center of said support and adapted to be moved outwardly into engagement with a drum of a rotary member to be braked to produce a braking eflect, a pin carried by each I shoe, a pair of links each having one end pivotally connected to said pin, a pin connecting the other 5 end of one link to the support, a rotary actuator, a pin connecting the other end of the other link to the actuator pin, the pin of the shoe lying outwardly of and between the pins of the support and actuator, the end of the links connected to the support pins having slots receiving said support pins to provide a lost motion connection therewith, and a spring urging the link containing the slot to its innermost position.

5. A brake mechanism comprising a fixed plate having a substantially cylindricallateral extension, a plurality of brake shoes positioned around plate and for outward movement toward the brake drum and for limited circumferential movement in the direction of rotation of the druin froman inward retracted position, said pin and slot means being positioned adjacent to the middle of'the brake shoes, guide rings rotatably mounted on said extension, expanding means mounted on said plate between two of the brake shoes, pivot means operatively connecting the two brake shoes at points at one side or said pin and slot means-with corresponding ones of the guide rings and'with the coyesponding sides 0 said expanding'mean's, levermeans operatively connecting the said two brake shoes with adjacent portions of the said corresponding rings at points at the opposite side of said pin and slot means, and spring means operatively connected between the ends ofithe two brake shoes opposite said expanding means for retracting the brake shoes toward initial position upon contraction of said expanding means.

6. A brake mechanism according to claim 5 wherein toggle link means is operatively connect- .05 pin and slot means, and said lever means being proportioned to permit the brake shoes to move in a substantially radially outward direction and toward the direction of rotation of the brake druni' when said expanding means is'expanded and the 'fore end of at least one or the brake shoes engages the drum, whereby a servo action of. the brake shoes is produced.

- .-EMIL ZIPPER. 

